April 2017 Service and Repair ManualBoom ComponentsPart No. 1272854 GTH-844 23How to R eplac e the Extension C hai nsHow to Replace the ExtensionChainsNote: Perform this procedure on a firm, levelsurface with the boom in the stowed position andthe wheels chocked.1 Start the engine and allow the engine to idle.2 Raise the boom to a horizontal position.3 Fully retract the boom.4 Turn the machine off and remove the key fromthe key switch.5 Working at the fork end of the boom, loosenthe fasteners securing the single-chaintensioners to the top of boom tube number 1.After noting the orientation and assembly orderof the components, remove the fasteners andpull the tensioners free of the boom. Refer toIllustration 1.1 extension chains2 single-chain tensioner3 boom tube number 14 boom tube number 25 boom tube number 36 Select a chain tensioner. Remove the bow tieclip securing the chain anchor pin to the chainassembly. Remove the chain anchor pin fromthe assembly and remove the chain anchorfrom the tensioner assembly.7 Repeat this procedure, beginning with step 6,for the other chains.8 Working at the fork end of the boom, select achain. Securely connect a 30 foot / 10 m lengthof rope to the end of the chain. Securely tie offthe other end of the rope to the boom structure.9 Remove the inspection cover from the pivotend of the boom and locate the chain anchorsof the extension chains at the top of boom tube3.10 Remove the fasteners securing the extensionchain anchors to the boom tubes.11 Working at the pivot end of the boom, pull thechain out of the boom.Note: Rope coming loose from the chain duringremoval may result in a difficult reassembly. Besure the rope is securely attached to the chain andboom structure before pulling the chain out of theboom.12 On a workbench, remove the bow tie clipsecuring the chain anchor pin to the chainassembly. Remove the pin and chain anchorpin from the assembly.13 Install the chain anchor, pin and clip onto thenew chain.14 Remove the rope from the end of the old chainand securely attach the rope to the new chain.
